Breather



May 26, 1942. H. M. ACLY 2,284,354

' REATHER Filed June 18, 1940 Ihven tor: Harry M. Ac \y,

by FM 5. z

His Attorhey.

Patented May 26, 1942 1 i BBEATHER Harry M. Acly, Pittsfield, Mass, assignor to General Electric Company, a corporation of New York Application June 18, 1940, Serial N 341,150

5 Claims.

The present invention relates to breathers and while it is not necessarily limited thereto, it is particularly applicable for use with liquid containing vessels such as oil filled transformer tanks.

In order to obtain high insulation levels for electrical apparatus such as a transformer, the assembled unit is thoroughly baked and dried so as substantially to remove all moisture therefrom. The unit arranged within a tank is then covered with an insulating oil having as one of its functions the prevention of absorption of moisture by the insulation. It is not always feasible to seal the vessel in a liquid tight manner and; in such instances, provision must be made to allow for expansion and contraction of the insulating "liquid with variations in temperature of the apparatus under varying load conditions. A breather may be provided in an opening in the tank wall above the normal liquid level therein establishing communication between the space above the liquid level and atmosphere. The breathers commonly used heretofore were generally supplied as separate units to be attached to the transformers by the customer after the transformers were installed, since they permitted leakage of a considerable quantityof oil from the tanks during handling and shipment. To prevent the loss of oil from the tanks prior to the installation thereof, the tank-vent openings were provided with special devices so designed as to minimize the splashing of oil therethrough. Such devices, however, included relatively small orifices and due to the high velocity of air passing therethrough, the abrupt changes of air temperature at the orifices would cause condensation of moisture from the air within the tank which moisture would contaminate the insulating liquid and be absorbed by the solid insulation. This might not be serious over a short period of time, but, as has been occasionally observed, customers afterreceiving a transformer so equipped may fail to replace the shipping tion for the vessel during the normal operation of enclosed apparatus.

For a better understanding of my invention,

attention is directed to the following description and the claims appended thereto taken in connection with the accompanying drawing, the single figure of which is across sectional View of a 7 liquid containing vessel provided with a breather device constructed in accordance with the invention.

Referring to the drawing, It indicates a vessel or tank containing a liquid H such as insulating oil within which may be immersed an electrical apparatus such as transformer l2. The tank is provided with a cover l3 suitably clamped thereto as by bolts Id. The cover I3 is provided with an opening preferably adjacent one edge to which is secured a breather device of my invention generally indicated at l5.

The breather includes an outer cylindrical casing it which is closed at its upperand open at its lower ends and is suitably secured as by a 1 weld H to the cover around the periphery of the opening. concentrically arranged within the casing I6 is an inner casing it having an annular shoulder 19 between the upper portion and the enlarged lower portion, the outside diameter of which is substantially equal spacer blocks 24 and 25. The upper block 24 is suitably secured as by welding to the outer casing and is threaded for cooperatively receiving the end of the axially extending stem or bolt 25. Within the enlarged lower portion of the inner casing is a disk 21 having a relatively large central valve opening 28 therein, which disk is held against the under side of the shoulder l9 by means of a cylindrical spacer 29 arranged between the disk and a baffle plate 3|. The baffie plate 3| is provided with a plurality of radially arranged openings 32 and is maintained in a spaced relation by washer 33 from the lower baffie plate 34 which is secured upon the lower end of bolt 26 as by nut 35. The outer edge of plate 34 is maintained in a spaced relation from the adjacent lower edges of the casings l6 and I8 bya plurality of spaced struckout portions 36. Slidably arranged upon the boltv 25 and within the space between the disk 21 and the bafiie plate 3! is a float valve 38 the upper surface of which lowest portion of the space between the inner and.

outer casings. Suitably secured within the opening 4! is a length of pipe G2 extending substanshown are merely illustrative and that the in-- tially horizontally outwardly beyond the edge of the tank cover l3 and provided at the end with a downwardly extending elbow G3. Threaded into above the normal liquid level therein,

" slidably arranged on' said stem for closing said the downwardly facing open end of the elbow 43.

is a screen disk M for preventing the entrance of insects or other foreign matter into the.

breather and tank.

The breather device as described is suitable for installation onto the tank at the factory. During the-shipment of the apparatus and handling thereof incident to the installation of the transformer, the oil may be splashed around considerably within the tank without appreciable leakage. The force of the liquid waves striking against the breather opening will be materially reduced by the .lower :baflie plates 34 and 3|. edge of the baffie plate 34 and upwardly through Any liquid, however, passing around. the

the openings 32 of disk 31 into the space thereabove will cause the float 38 to rise and close the opening 28 in the" valve plate 2]. Some liquid of course may escape throughv the valve opening 28 into the chamber-thereabove within the inner casing [8 before the float 3B is moved to the fully closed position. Such liquid, however, is retained within the inner .casing 18 until such time'as'the float 38 drops to its lower position when the liquid will be returned to the interior of the tank.

It will be observed thatthe disk cap 23 is spaced between the inner and outer casings so ,that its temperature will benearer that of the air leaving'the transformer than that of the outside atmosphere. ,Moisture will therefore not condense on its surface to the same extent as on the inside of the outer casing l6 as the outer Any condensate which T in the inner casing, into thespace betweenthe 1 inner and outer casings and outwardly through .valve opening upon a predetermined abnormal rise of liquid level in said vessel, an inner casing surrounding said valve opening and having vent passages in the upper portion thereof, and a vent opening'in the lower portion of said outer casing. I

2. A breather for a tank containing a liquid and having an opening in an upper wall above the normal liquid. level therein, a casing secured to saidwall aroundsaid opening, a plate extending across the interior of said casing and having a relatively'large central valve opening therein, a stem secured to said casing and extending axially through said opening, afloat valve slidably arranged on said stem beneath said valve opening, means spaced from the inner walls of said casing defining a chamber above said valve opening and having a vent opening in the upper part thereof, and a vent opening in said casing.

3. A breather for applicationv to an opening in a wall of. a liquid containing tank, said breather comprising a casing to be secured around said opening and open at its bottom end, means defining avalve opening in said casing, a stem. secured to-said casing and extending axially through said opening, a float valve slidably arranged upon said stem beneath said opening, a .vent opening in said casing on the outer side of said valve opening,'said means having a vent opening in the upper portion thereof and spaced from said vent opening in said casing; r Y

4.. In combination a vessel containing aliquid, an opening in a wall of said vessel above the normal liquidlevel therein, a float movably arranged adjacent said opening for closing said opening upon the approach of the liquid level thereto, means defining a chamber around said opening'on the outside of said'wall for retaining the vent opening 4|, :pipe 42, and through the elbow 43 and screen 44. In order to prevent such moisture from seeping between the adjacent walls of the inner and outer casings atthe' adjacent lower portions thereof, it is preferred. that they be brazed or soldered together in order it will ordinarily be stationarily 'mounted, the' to effect a fluid tight sealtherebetween.

During the operation of the transformer, when Having described the principle of operation or.

my invention in what I now consider to' represent a preferredembodiment thereof, 'I desire to have it understood that the specific details liquid working past said float through said opening, vent openings in the'upper portion of said means, a casing surrounding said means and having a vent. opening in the lower portion thereof, and means arranged above said ventopenings in the upper portion of said means and spaced from the inner surface of :said casing. 5. A breather for a vessel containing a liquid and having an opening in an upper wall thereof above the normal liquid level therein, said breather comprising an outer casing and an inner casing sealed together at adjacent lower edges and adapted to be secured to said wall about said opening, said inner casing having a vent opening in the upper part thereof for communicating with the interior of said vessel through said wall opening, and-a cap secured in a spaced relation between said casings and extending over said ventopening and a vent opening in said outer casing below said cap.

HARRY M. ACLY.

CERTIFICATE OF CORRECTION. Patent No. 2,28L ,5 L May 26, 19152.

' HARRY M; ACLY.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, sec-- 0nd column, line 1 5, claim 5, after "opening," and before "said" insert and means arranged between said valve opening and said vent opening for preventing liquid leaking past said valve from escaping through said vent opening,-- and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 28th day of July, A. 1). 1912.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents. 

